However the prominent part the Germans had in these achievements as well as the lofty idea of the Roman Empire then prevailing led Otto I, the Great, to require Harold to recognize him as "advocatus", or lord protector of the Danish church, and even as "Lord Paramount".

Formerly, during the canonization process of the Roman Catholic Church, the Promoter of the Faith (Latin: Promotor Fidei), or Devil's Advocate (Latin advocatus diaboli), was a canon lawyer appointed by the Church to argue against the canonization of the candidate.

While there is no record of a university degree in either subject, his official duties as city orator and advocatus at Metz implied legal training, and the city's records refer to him as a doctor of laws.